Field of the Invention
This invention relates generally to the field of computer processors. More particularly, the invention relates to an apparatus and method for sampling pattern generation for a ray tracing architecture.
Description of the Related Art
Ray tracing is a graphics processing technique for generating an image by traversing the path of each light ray through pixels in an image plane and simulating the effects of its incidence upon different objects. Following traversal calculations, each ray is typically tested for intersection with some subset of the objects in the scene. Once the nearest object has been identified, the incoming light at the point of intersection is estimated, the material properties of the object are determined, and this information is used to calculate the final color of the pixel.
A frequent occurrence in the more advanced ray tracing algorithms such as area lights, ambient occlusion, glossy reflections, global illumination, is the integration of the radiance arriving at a point. This is done by summing the results from spawning multiple ‘random’ rays (e.g., 64) to sample the environment. These samples need to obey some probability distribution function, exhibit a degree of randomness from pixel-to-pixel, but be repeatable from frame-to-frame.